Introduction

1. Introduction Rice crop is sensitive to water stress causing reduction in quality and quantity of yield. Therefore management of irrigation is of uttermost importance and must be practiced from the nursery stage of rice. A few amendments in cultural practices can help in economic management of irrigations. The cultural practices include, ploughing by mould-board plough and puddling twice by disc harrow improve the water use efficiency and yield. Maximum water-use efficiency for rice can be obtained with check basins type of irrigation design of size 250-300 square meter area. .

2. Nursery Irrigation Strategies • Seedbeds must be located away from electric light in a fertile field that is easy to irrigate & drain. It is estimated that 150-200 mm of water is needed for nursery bed preparation and 250-400 mm of water to raise the seedlings. • Rice nursery should be watered daily in the morning and evening. Water should be gently sprinkled over the bed with a garden rose can. Nursery can also be watered by letting in water into the canal surrounding the nursery bed. • Standing water to a depth of 2-3 cm should be maintained at least 2-3 days before uprooting the seedlings.

3. Nursery Irrigation Strategies • Wet Bed Nursery : • It is practiced in areas with adequate water supply. Nursery site should be without shade and with adequate irrigation and drainage. • Soil should be thoroughly puddled and leveled. Drainage channels must be constructed between seed beds for proper removal of water. Before sowing, nursery is irrigated and excess water drained. • Allow enough water to saturate the soil for 3-5th day after sowing. From 5th day onwards increase water depth of 1.5 cm to 2.5 cm depending on the height of seedling.

4. Nursery Irrigation Strategies • Dry Bed Nursery • The site should be free from shade and with adequate irrigation facilities and the nursery should be maintained without any moisture stress. Beds are separated by irrigation channels 30 cm wide . • Allow the water to run in channels so as to maintain soil moisture at saturation. Maintain soil moisture at optimum level for 20-30 days. Regulate the water supply, if necessary, to control the rate of seedling growth.

5. Nursery Irrigation Strategies • Modified Mat Nursery • Sprinkle water immediately to soak the bed after sowing. Protect the nursery from heavy rains for the first 5 Days after sowing. • On the 6th day after sowing, flood the nursery with sufficient water and maintain 1 cm water level around the mats. • Later, water the beds until 15 days after sowing as and when needed. Keep the beds sufficiently moist. Drain the water 2 days before lifting the seedling-mats.

6. Nursery Irrigation Strategies • Dapog nursery: • In case of Dapog Nursery, the site should be a leveled and the area should be near the water source. • The beds should be watered lightly with a rose can and pressed down lightly by hand or with a wooden flat board twice a day for 3 to 6 days. This keeps roots of seedlings in contact with water retained on the surface and prevents them from drying. • From 7th days of sowing 1 to 2 cm water should be maintained in the seed beds for optimum growth of seedlings in a short time.

7. Dry bed Rice nursery Wet Bed Rice Nursery Dapog nursery of Rice Modified mat nursery in Rice